edema and bipap

Currently trying to find all I can about edema as a side effect of using cpap/bipap. It seems to be a very rare side effect. I've found two published letters so far in Sleep Medicine Journal (search for edema and cpap) that document this as a rare case. I'll include the links, but one has to pay to get them. If anyone has any information that has been published about this side effect, please post!

Use the search function at the top left hand side. There are many posts on this issue on the board already.

Hi,
Yes, I've searched through most of the different forums out there, it seems to be a true, but rare side effect, but mainly anecdotal (no scientific study done as far as I can tell). I'm specifically looking for any studies or published data to show to doctors here (they keep saying they have never heard of this) or the opposite, that the machines generally reduce edema. I'm also interested in if edenais a problem, bipaps seem to help (in our case it does not make a difference) or if folks have taken either diuretic or heart medication, and then go on to successfully use bipap without getting the edema. So, any ideas welcome. Always good to find information on forums like this!

Re: C-PAP induced Edema
by Lindywise on Sat Aug 13, 2011 8:39 am

I too noticed swelling in my feet after the first night of using the CPAP machine. After trying several, and finally finding a well-fitted full-face mask, I now find I have severe swelling all over my face, legs, neck, feet, eyes, etc.

I've NEVER EVER had edema of any kind before, nor heart nor lung problems of any kind (got a clean bill of health this year after all kinds of pre-surgery tests for a torn meniscus). One of those tests was for sleep apnea hence the diagnosis and resulting CPAP. My energy is returning and morning headaches have disappeared!

I have noticed throughout trying the various masks, the more the leakage the LESS the edema.

After researching forums about this, I've found several posts/reasons others have given:
1. Too high humidity on the heated humidifier.
2. Diastolic dysfunction causes excess fluid to build up in the lungs; the cpap may be pushing this excess fluid out of the lungs, causing the edema.
3. Too much pressure exerted on the exhale with a resulting affect on the heart's functionality resulting in edema (some noted edema continues even with the use of a BiPap machine).
4. Inactivity during sleep.
5. Gulping air (aerophagia).

I do have the humidity set high (5) but that's because I live in an arid region. I am a very active sleeper even with the CPAP. I don't believe the exhale is my problem as I've always had a fan pointed right at my face at night (due to the hot arid region of the country I am in) and am very comfortable with using the CPAP. I've tried both the full-face and nasal-only masks (prefer the full face) so its not a matter of gulping air.

I am going to try reducing the humidifier and talk to my doctor about diastolic dysfunction. There obviously is a connection with the CPAP as indicated by the numerous threads of others, and directly related to using the CPAP in my case as the edema began immediately upon use of the machine.